Graphynes for Water Desalination and Gas Separation

Selective transport of mass through membranes, so‐called separation, is fundamental to many industrial applications, e.g., water desalination and gas separation. Graphynes, graphene analogs yet containing intrinsic uniformly distributed pores, are excellent candidates for highly permeable and selective membranes owing to their extreme thinness and high porosity. Graphynes exhibit computationally determined separation performance far beyond experimentally measured values of commercial state‐of‐the‐art polyamide membranes; they also offer advantages over other atomically thin membranes like porous graphene in terms of controllability in pore geometry. Here, recent progress in proof‐of‐concept computational research into various graphynes for water desalination and gas separation is discussed, and their theoretically predicted outstanding permeability and selectivity are highlighted. Challenges associated with the future development of graphyne‐based membranes are further analyzed, concentrating on controlled synthesis of graphyne, maintenance of high structural stability to withstand loading pressures, as well asthe demand for accurate computational characterization of separation performance. Finally, possible directions are discussed to align future efforts in order to push graphynes and other 2D material membranes toward practical separation applications. Graphynes, allotropes of graphene yet containing intrinsic uniform pores, are attractive for membrane‐based separation applications including water desalination and gas separation. A comprehensive overview of various graphynes for these separation applications is presented, focusing on their predicted outstanding performance as well as remaining challenges in order to assist the future design of these membranes.